Method for Forming Fine Patterns of Semiconductor Device

A method for forming fine patterns of a semiconductor device, the method comprising:

• forming a first pattern having a line type that connects an active region of a cell region in a longitudinal direction over an underlying layer;
• forming a spacer insulating film over the resulting structure including the first pattern;
• forming a planarized gap-fill insulating film that exposes the spacer insulating film;
• removing the spacer insulating film using the gap-fill insulating film as a mask to form a second pattern between the first pattern;
• forming a first photoresist pattern that defines a contact hole for separating the first pattern and the second pattern;
• reducing a critical dimension (CD) of the contact hole;
• etching the first pattern and the second pattern using the first photoresist pattern as a mask;
• and,
• etching the underlying layer using the etched first and second patterns as a mask.